In Applicant's co-pending application U.S. Ser. No. 10/696,583, filed Oct. 30, 2003, hereby incorporated by reference in its entirety, there are disclosed novel structural concrete insulating panels (SCIP) having built-in screeds and methods of making the same that allow for non-skilled labor to assemble and finish the panels for use in the construction of dwellings, buildings, residences, and the like. These panels are currently sold commercially under the tradename “MetRockSCIP®”.
A SCIP is a composite panel with an insulating core, which, in the case of MetRockSCIP®, is a core of EPS (expanded polystyrene plastic) foam. The insulating core is then enveloped with a reinforcing cage. In the case of the MetRockSCIP® the reinforcing cage is a welded wire truss with a welded wire face mesh and the two, the truss and the face mesh elements, being held together with mechanical fasteners, specifically wire C-rings. This panel assembly, of the insulating core and the reinforcing cage, is then finished with a cementitious skin, or shell, on each face. Because of the nature of the wire mesh face and the positioning of the mesh and the truss, which caused the welded-wire face mesh to be centered in the cementitious shell, the final panel is able to behave in a composite manner. In other words, because the face mesh and the cord and web ends of the truss are anchored in the two shells, the wire reinforcing cage allows the two shells to work together, fundamentally placing one shell in compression while the other goes into tension, and the whole is a composite panel, with all the parts working together to bring about the resultant structural behavior.
The behavior of the panel is somewhat analogous to the behavior of steel “I-beams” or wide-flange beams. The web connects the flanges of the beam to each other and the whole is able to act as a composite, with overall better structural behavior far greater that any or all of the parts could demonstrate acting alone. Similarly, in the MetRockSCIP® panel the shells are connected to each other by the truss, allowing all to work together. The mesh reinforces the shells and better anchors the truss in the shells. The core allows for easy fabrication of the shells and prevents the panel from becoming a solid mass of concrete, which would change it from a composite shell panel to a simple solid concrete panel, which would greatly reduce the structural performance of the panel.
Fundamental to SCIP panels is the known behavior of concrete beams and columns. It is well known and documented and is the fundamental concept behind all concrete beam and column engineering that the forces in a concrete column and beam move to the outer surface of the member, leaving the center of the member with little to no force in it. A typical design drawing of a concrete beam will show a wave passing from the top of the member to the bottom of the member and back, for the length of the member. This is to symbolize the compressive force in the top of the member and the tension force in the bottom of the member. As the wave curve passes through the center of the member we commonly speak of it passing through “zero” force or that the center is “quiet” as to forces. From this we understand that the center of the member has very little forces in it, and, hence, the steel reinforcing in a concrete beam or column is at the edge or surface of the member and little to no reinforcing is in the center of the member. The mass of the concrete in the center of the member serves principally to simply hold the outer surfaces to each other so that the loads can be transferred back and forth, as shown in a typical design wave curve.
Because beams and columns are typically created through the process of “forming and pouring” there is really no practical way of eliminating the concrete in the center of the member. Further, concrete as a material is best a compression behavior and needs the steel reinforcing bars to do a good job of resisting tension forces. It has long been known that the mass of concrete added much weight to the member and that significant portions of the reinforcing steel added to the columns and beams was there simple to overcome the added mass of the center volume of concrete. The advent of the SCIP panel, in the late 1960's was a significant advance in concrete construction.
The SCIP panel presented a way of making a reinforce concrete member, but without the disadvantage of the large mass of concrete in the center of the member but with a means of still connecting the two outer reinforced surfaces and allowing them to pass their forces back and forth to each other. The idea of placing a lightweight core in the center of a reinforcing matrix which would have sufficient connectivity between the outer surfaces to allow the forces to pass back and forth between each other, while doing so without having the large dense mass of concrete in the center of the member was indeed novel. Various means of making up the reinforcing cage and of placing the core in the center of the panel have been devised and have received patents.
Once the reinforcing cage was fabricated with the core being held in the center of the reinforcing cage, the application of the cementitious shells was rarely, if ever, addressed in any prior art. It was simply left to the user to decide on how to accomplish that aspect of the final composite panel. Various means of applying the shells have been employed: placing the cage inside a form and casting the shells by pouring concrete between the form on each face and the core; hand applying/troweling-on the shell material; spraying with any of the several plaster, air-placed concreting, shotcreting, and guniting methods; have all been used successfully.
Over time, the use of air-placed methods has become the predominant method of applying the shell material to the SCIP panel. This means that some method of pumping and spraying with air pressure is used to convey the cementitious material onto the panel. This results in a relatively fast method of getting the material onto the panel and the resulting economy of this speed is highly desirable. However, there is one very significant drawback to this method—the finished surface of the panel. When spraying the material onto the panel, the material ends up being quite rough and can have significant highs and lows to the surface. This results in the need of skilled craftsmen to smooth out the surface after the spray equipment has applied it. It is well known that the plastering trade is a declining trade in the US, having been nearly totally replaced by the use of gypsum wallboard. Because of this there are fewer and fewer skilled craftsmen who can effectively finish a sprayed wall. It may well be that this single fact is the reason that there are to date no successful SCIP panel enterprises in the US while there are many, many SCIP plants around the world. Every SCIP panel plant ever opened in the US has failed, without exception. Conversely, there are SCIP panel buildings being built daily in Mexico and around the world, where plastering skills are the norm.
It is specifically to this issue that the MetRockSCIP® panel addresses itself. As disclosed in Applicant's co-pending application U.S. Ser. No. 10/696,583, filed Oct. 30, 2003, the face mesh of the MetRockSCIP® panel includes deformations in the shape of V-shaped ridges, or “screeds,” that allow an unskilled worker to quickly and accurately flatten the sprayed surface of the shell. By simply drawing a flat edged tool, known in the trade as a “rod” or “knife” along the built-in “screeds” created by the deformations in the MetRockSCIP® face mesh, the worker can quickly true up the surface and achieve results approaching the work of a skilled craftsman.
The MetRockSCIP® is a code conforming Structural Concrete Insulated Panel System that has been designed for structural walls, floors and roofs. MetRockSCIP® is a seamless, monolithic structure and meets the long term needs for affordability (as low as $10 per sq. ft), sustainability (fire, hurricane, tornado, earthquake, termite resistant), extremely energy efficient (R-40 Performance), and green (all recycled components). The MetRockSCIP® has been designed in the U.S. specifically for the U.S. Residential and Commercial markets. Non-skilled labor is all that is required for the assembly, erection and to mix, pump, spray and finish the plaster cement skins onto the panel.
The MetRockSCIP® qualifies as a green building system because all of the components of the MetRockSCIP® are recycled products. The 3/16″ diameter wire trusses (show the photo of the stack of truss wires) are made of recycled steel. The 1″×1″×14 gauge wire mesh members, which feature the novel screed ridges that are made into the mesh, are made of recycled steel. The wire “C” rings, which attach the mesh to the trusses, are made of recycled steel. The foam insulation, which can be from 2″ up to 12″ thick, are made of recycled EPS beads. Also, the cement plaster of the commercial embodiment contains up to 30% fly ash, which is a by product of coal.
MetRockSCIP® Technology is presently available for license. Included in the license package is the Portable Assembly Jig Press which allows for panels to be assembled right on the job site if desired, Portable press brake, Blastcrete Mixer/Pump with hose package, air compressor, all assembly and erection tools, and complete training and certification. Packages vary from $60,000 up to $100,000 for protected territories, and there are currently no license or franchise fees. The license cost is directly related to the equipment that chosen for a desired license package, and the required territory. The MetRockSCIP® conforms to all local building codes.
MetRockSCIP® assembly, erection, and the cement plaster application is quick, easy and does not require skilled labor. Two unskilled laborers can assemble a Metrock Panel in five minutes using the portable jig press. Once assembled dowels are drilled and grouted to anchor the panels to the foundation. The panels are then assembled and the cover mesh is attached to cover the seams between the panels. Simple tools are used to hold the panels straight and square. Utilities are then installed prior to spraying. Once the panels have been erected, 1″ of plaster cement is then spray applied to each side of the panel to make the panel structural. Approximately 6-8 square feet of panel can be covered with 1″ of cement plaster per minute. The novel screed ridges, which are made into the wire mesh serve as visual depth screeds for the nozzleman while spraying the cement plaster, then serve as a mechanical screed for the worker to cut the cement plaster flat and straight without the need for skilled labor. A final 3/16 inch finish coat is then spray or trowel applied for the desired finish.
In sum, the MetRockSCIP® is the most versatile, affordable, sustainable, energy efficient, green composite building envelope ever introduced in the U.S. MetRockSCIP® lowers insurance rates and utility bills by over 60%, plus there is ZERO maintenance. Additional details and video demonstrations are available for viewing at www.MetRockSCIP.com.
While the cost of assembling an entire structure using the MetRockSCIP®methods and materials is considerably cheaper and quicker than building the structure using conventional means and conventional materials, the resultant structure includes interior and non-load bearing walls that possess the structural and impenetrable features of the MetRockSCIP® in areas where such strength and protection is unnecessary or superfluous.
However, if conventional interior building materials for non-load bearing walls are used, many of the problems in the art the MetRockSCIP® was intended to overcome are again encountered, e.g., need for source of lumber, etc.; need for skilled labor and tradesman; and/or resultant time consumption due to required framing, insulating, finishing, etc.
Accordingly, there exists a need in the art for allowing interior and non-load bearing walls in a SCIP structure to be used that does not result in the drawbacks presented by conventional building materials and techniques. Moreover, the foregoing underscores the need in the art for an integrated building system which allows for building areas, such as exterior walls, roofs, etc, and other load bearing interior walls to be constructed of SCIP panels providing the strength and imperviousness desired for the building, while allowing interior and non-load bearing walls to be constructed on non-structural materials that may be finished with a matching coat or otherwise be compatible when assembled in the framework of the SCIP structure.